Abstract
In this study, the seismic performance of concrete-steel composite moment frame structures equipped with seismic retrofitting systems such as seismic reinforcement, base isolators, and bracing members, which are typical earthquake damage mitigation systems, is evaluated through nonlinear dynamic analyses. A total of five frame models were designed and each frame model was developed for numerical analyses. A total of 80 ground acceleration data were used to perform the nonlinear dynamic analysis to measure ground shear force and roof displacement, and to evaluate the behavioral performance of each frame model by measuring inter-story drift ratios. The analysis results indicate that the retrofitting device of the base isolator make a significant contribution to generating relatively larger absolute displacement than other devices due to flexibility provided to interface between ground and column base. However, the occurrence of the inter-story drift ratio, which is a relative displacement that can detect the damage of the structure, is relatively small compared with other models. On the other hand, the seismic reinforced frame model enhanced with the steel plate at the lower part of the column was found to be the least efficient.
